I think the problem is that people expect the marriage to make them happy, or as it is sold "the other person that comes and all your problem cease to exist" I

I think the problem is that people expect the marriage to make them happy, or as it is sold "the other person that comes and all your problem cease to exist" I don't think marriage or anyone else will make you happy in the long term, you have to do the work yourself. A supportive partner is a great thing but not a solution. I believe many marriages fail because people eventually realize there is no magic wand solution to their own problems.